Career Longetivity- Anand GM in 1988 still playing, Kasparov GM in 1980 retired in 2005

But the thing that tilts the scale in Anand's favour is "He has played the game in the era of computers which can beat the top human players and therefore the qualtiy of competivie chess played by him throughout his career, both by him and his opponents is much superior than ever before".

Except, dale, that in head-to-head match-up, Kasparov destroyed Anand. Kasparov's highest rating is higher than Anand's highest rating. And if you believe the inflationists, that should not be possible.

For a brief period from about 2003-2005, I would have bet on Anand to win a match against Kasparov. Unfortunately, they only played a handful of games during that time as Kasparov was heading towards retirement.

By 2008, Anand was clearly better than Kasparov. But Kasparov at his peak was better than Anand was at his peak.

Anand's highest rating was 2817. Kasparov's was 2851.

Since you are so reliant on ratings does this mean you believe Carlsen is the best player ever !? His rating is the highest ever afterall ...

Now that Carlsen has won the World Championship, yes. I believe Carlsen is the best player ever. His ratings and his title prove it.